1. Technical Field
The present disclosure relates to a receiving apparatus that controls gain in accordance with electric power of a received signal.
2. Description of the Related Art
Standardization of a communication standard of wireless LAN (Local Area Network) such as IEEE (The Institute of Electrical and Electronics Engineering, Inc.) 802.11ad is in progress. IEEE802.11ad employs an access control method called CSMA/CA (Carrier Sense Multiple Access/Collision Avoidance).
In CSMA/CA, a receiving apparatus detects a signal present in a wireless transmission path and adjusts gain for amplifying the detected signal so that a band of fluctuation of the detected signal falls within a dynamic range of an ADC (Analog Digital Converter). In IEEE802.11ad, a training sequence called a preamble is provided at the start of a packet, and a receiving apparatus executes automatic gain control (AGC) by using the preamble.
As a technique for rapidly converging AGC in a restricted preamble section, for example, Japanese Unexamined Patent Application Publication No. 2005-278017 is known. A wireless communication device described in Japanese Unexamined Patent Application Publication No. 2005-278017 stores an optimum AGC gain value of a past communication and sets the stored gain value as a standby gain value for each AGC circuit during a standby period, thereby shortening a convergence time needed before determining an optimum gain value at the restart of communication.